1. Field of the Invention
The present invention generally relates to KVM switches, KVM systems and computer readable mediums.
2. Description of the Related Art
A KVM (K: keyboard, V: video, M: mouse) switch includes a terminal emulator connected between a plurality of servers and peripheral devices such as, mouses, keyboards and monitors, as disclosed in U.S. Pat. No. 6,567,869 (KVM SWITCH INCLUDING A TERMINAL EMULATOR), which is hereinafter referred to as Document 1. The KVM switch has a function of converting video data received from a port of a selected server into an analog video data, which is then supplied to a monitor. The port may be a serial port or a USB (Universal Serial Bus) port.
There is known a monitoring apparatus that monitors a processing device having a pointing function such as a mouse or keyboard, as described in Japanese Patent Application Publication No. 2006-99498, which is hereinafter referred to as Document 2. The monitoring apparatus has a quasi-mouse and a quasi-keyboard, applies a signal to the processing device to be monitored. The signal is a mouse or keyboard signal from the quasi-mouse or the quasi-keyboard. The monitoring apparatus determines whether there is a change in image information processed by the processing device or not. When there is no change in image information, the monitoring apparatus determines that a problem has occurred in the processing device.
In the KVM switch described in Document 1, when a problem occurs in the selected server and causes the server to freeze up, video data indicating freezing up is displayed on the monitor. Thus, a user is urged to switch on the server again in order to restart the server.
When the user who watches the monitor is at a distant place away from a place where the server is set, the user is required to ask an administrator to switch on the server again. However, this is bothersome.
It is now assumed that the KVM switch described in Document 1 is combined with the art described in Document 2, in which the monitoring apparatus transmits the predetermined signal to the monitored device for detecting a problem therein. In this case, it is necessary for the KVM switch to transmit the predetermined signal to the server for detecting a problem in the server. However, this increases the load of the KVM switch. Further, when the user who watches the monitor is at a distant place away from a place where the server is set, the user is required to ask the administrator to switch on the server again. However, this is bothersome.